3-18-2016, NY Times --

THE ROAD TAKEN
The History and Future of America’s Infrastructure
By Henry Petroski
Illustrated. 322 pp. Bloomsbury. $28.

Henry Petroski’s “The Road Taken: The History and Future of America’s Infrastructure” is really two books in one. It is, first, a history of infrastructure from the Appian Way to the present. It also promises to be a guide for the present, helping us “better understand what is involved in making key choices that we are faced with today.” The book intermittently succeeds in both guises, though it takes some detours along the way.

Petroski, a professor of both engineering and history at Duke and the author of such books as “The Pencil” and “The Evolution of Useful Things,” brings an eye for the little things: what kinds of guardrails are best, how roads can be made safer through better signage, which paving materials last longest. One of his key lessons is that small thinking can be a virtue, because the history of infrastructure is a series of experimental and incremental improvements.

Local governments tried endless variations of asphalt and concrete before developing paving surfaces that didn’t produce excess dust or deteriorate quickly under rain and snow. They gradually built longer bridges, learning from earlier designs that worked, and that didn’t. They tried out different paint colors for lane markings, finding the ones that drivers could see best.

This little-things perspective is needed at a time when America’s infrastructure agenda is simultaneously characterized by grandiose ambitions and limited budgets. Money is tight, and infrastructure needs are going unaddressed. At the same time, despite funding limitations, politicians have a tendency to fall in love with novel, pathbreaking, expensive projects that frequently go astray, resulting in arguments against spending more on infrastructure.

Petroski devotes one chapter of his book to the new eastern span of the San ­Francisco-Oakland Bay Bridge, which opened in 2013, nine years late and $5 billion over budget. “With uniqueness also come uncertainties — of complications during design and construction and of cost,” he writes. Replacing an old bridge with seismic problems could have been done fairly easily and cheaply by building a simple viaduct. But politicians wanted a “signature span,” and for a variety of aesthetic reasons they chose to build a single-tower, self-anchored suspension bridge — a relatively rare design. The proposed bridge would be the longest of its kind in the world.

But self-anchored suspension bridges lack the massive anchorages at each end that are typical for suspension bridges. Instead, the cables would be anchored to the deck itself. Because of the desire to add a cantilevered bike lane, the bridge would also have to be wider on one side than the other.

These shifting specifications added greatly to time and cost, obliterating the justification that had led politicians to choose to build a new bridge in the first place: that it would cost about the same amount as retrofitting the old span to be safer in earthquakes. And in the end, the single tower wasn’t built quite upright, and the technique used to straighten it after construction weakened the steel rods inside it, calling into question how seismically sound it was anyway.

Politicians aren’t drawn to megaprojects just because they believe the initial rosy cost projections and therefore underestimate the risk of complications. They also see an opportunity to build their legacy: It’s more fun to say “I built that bridge” than “I retrofitted that bridge.”

In New York, we have just celebrated the opening of the world’s most expensive train station, a $4 billion replacement for an existing subway terminal at the World Trade Center. Gov. Andrew M. Cuomo has also revived a decades-old plan for a miles-long tunnel under Long Island Sound. Yet nobody, including the governor, has found a way to fund the Metropolitan Transportation Authority’s five-year capital plan, filled with more quotidian projects like signal upgrades, which do not lend themselves so well to ribbon-cutting photo opportunities.

Read the rest of the story here: http://www.nytimes.com/2016/03/20/books/review/the-road-taken-by-henry-petroski.html?_r=0